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counterfriction writes "This month's issue of Symmetry, a magazine jointly published by SLAC and Fermilab, is featuring an article that points out the sometimes extemporaneous and unconventional solutions physicists have come up with in (and out of) the laboratory. From the article: 'Leon Lederman ... used a pocket knife, tape, and items on anyone's grocery list to confirm that interactions involving the weak force do now show perfect mirror symmetry, or parity, as scientists had long assumed.'"

You know, some experiments must be repeated 'til the result matches your expectation. But since neither music sales nor stem cells are involved... well, with a bit of squeezing we could press it into the "creation of the universe and all" corner.

Actually, even though you're joking, this is the essence of the scientific method. Hard science works because anybody can (and should, periodically) check that the assumptions are true now. There's no room for faith in the truth of past experiments.

An experiment which isn't repeated again and again by as many people as possible is a meaningless experiment.
That's one of the reasons why undergraduate physics students are given classic experiments to (re)confirm themselves in labwork.

You don't have to repeat it as many times as possible! That's just wasting time and money. Doing experiments with variations, to confirm what the limits of the theory are and testing related hypotheses is much more effective.

The real reason undergraduates get those classic experiments is to teach them how to do experiments, the limits of their instruments, how to record all relevant data, the difference between accuracy and precision, etc. The big experiment being done is actually on the students themselves, to see if they've learned to do reliable experiments. You absolutely do not want to do sensitive experiments with students whose reliability and even whose honesty have not yet been tested in lab work with known expected results.

Rereading my post, I think I only claimed it's to reconfirm the experiments themselves.

I'm not so much suggesting that anything they do should be published, I'm suggesting it's their job to verify the old experiments for themselves, because they (some of them) will be the scientists of tomorrow, and as such they are the witnesses of physics.

It would be a waste for researchers to replicate old experiments exactly, obviously. However it would be wrong for nobody to replicate old experiments (or their equi

I might be going off the deep end here, but the fact of the matter is, the universe is expanding quite rapidly and there is nothing that says that physics constants can not change over time. One "constant" that has changed and actually is not a constant at all, is the fine-structure constant (Read this to mean: the electric charge. ) The coupling of photons to electrons change, effectively changing the electric charge with distance. Hence, the fine-structure constant is known as a running-coupling constant. There are experiments under progress right now that are trying to measure the fine-structure constant from very-far-away galaxies, or back in time. Ok, maybe I am talking about cosmological scales here, but it would be funny if humans evolved, and some billions of years later, someone reading about some experiment like Rutherford's re-did it and got different results...

Back to the subject: yep, it is pretty crucial to get undergrads to repeat old experiments, especially ones like P-violation, Moessbauer, optical-pumping, muon-lifetime, which have all contributed to our current understanding of physics as a whole. Afterall, if they continue in physics, they might be stuck on experiments like mine, where one does not get data for the next "n" years. (I consider myself a physicist now for 10 years and have not been on a running and data collecting experiment yet. I am very happy that I got to do all those old-experiments in my undergrad years. Good old junior lab... )

One "constant" that has changed and actually is not a constant at all, is the fine-structure constant

Let's not be too hasty here. Changes in the fine structure constant have been proposed to account for some cosmological observations, but the evidence is spotty, with the best evidence indicating that it is NOT happening. See, for example,
http://www.newscientist.com/article.ns?id=dn7285 [newscientist.com]

there is nothing that says that physics constants can not change over time... and some billions of years later, someone reading about some experiment like Rutherford's re-did it and got different results...

There is a beautiful essay by Feynman about the classical rats-in-a-maze experiment, and how the scientist discovered that he had to change many conditions of the maze before the rats would learn how to run the maze themselves, instead of relying on other navigational information.

Feynman also comments that this scientist's work with rats was more or less completely ignored, and the rest of the field continued to run their rats-in-a-maze experiments the traditional old-fashioned way.

The thing about their story that got me was the fact that they decided they absolutely had to do this *right now* at 2am just to satisfy their own curiosity and were so self-absorbed that they killed the work a grad student had done in that particular lab in order to cannibalize his experiments so they didn't have to build everything themselves.

I'm sorry. That's not the mark of great scientists. That's the mark of self-important assholes despite the outcome.

Intrigued by the experiments of Madame Chien-Shiung Wu, Lederman called his friend, Richard Garwin, to propose an experiment that would detect parity violation in the decay of the pi meson particle. That evening in January 1957, Lederman and Garwin raced to Columbia's Nevis laboratory and immediately began rearranging a graduate student's experiment into one they could use. "It was 6 p.m. on a Friday, and without explanation, we took the student's experiment apart," Lederman later recalled in an interview. "He started crying, as he should have."

Hell I'm a grad student and I don't get treated like that. Dismantling someone's experiment out of some higher-ups whim is not what I would consider normal, or I'm just really lucky to have a supervisor that I can actually talk to instead of him expecting me to treat him like a royal subject or anything.

Now there's a lot of "don't-knows" in that little story, but that goddamn student is in the lab at an hour that I wouldn't consider normal working hours (on the weekend, no less), so it's probably safe to say that he/she's been working on that experiment for quite some time or simply just having a bad luck of getting elbowed all the time so there's no other hours available. Imagine waiting for a time slot in a lab and then when you're finally can get some work done, it's suddenly getting ripped apart by someone who has already elbowed your time many times over. If I were in that position, I would be considerably pissed and very likely to do something about it.

The point being, even if you're Einstein and Newton incarnate combined, you have no right whatsoever to do whatever you please to anyone else. Lederman should have the decency of helping the student to put his/her experiment back to the way it was before, it's very plausible that he has the ability to. However, judging from his tone of no regret in the interview, most likely he didn't care and just left the student to pick up the pieces of his brilliant experiment.

You're fairly lucky. These days, the "disassembly" goes on at resource allocation and funding time. Your equipment money goes to buy a professor a laptop, or to send some favored colleague to a conference to do a presentation and keep them on the tenure track, and you never even get to hear about it (Unless you're like me and had to fix their email, meaning they sent you the bounce messages or gave you deliberate access to their mail spool to fix it.)I hope Lederman did help the student out later, I really

I'll say he's lucky. Most grad students get treated the way a colleague of mine treats his more attractive female grad students. Except without the tenderness and condoms. And no breakfast or cab fare home.

Seriously, the treatment of grad students is something that bothers me about academia. Some of it comes from professors having been treated the same way when they were grad students, so now they feel obliged to pass the sh

It's accelerator physics. The beam, which is incredibly expensive to start up and maintain, runs 24-7. For many projects, beam time is scheduled months in advance, so if you get a slot at 3 AM Sunday morning you are certainly expected to be there.Most likely, he just happened to be the one on the beam at the time. "Ripped apart" in this case probably doesn't really mean disassembled. Probably they simply removed his equipment from the line so they could do their own experiment, but his equipment probabl

Genious is about using the spark when you have it. If you come in at 9 and take off just past 5 you're nothing but a corporate drone. I've worked both side and let myself be bogged down by administrativia to know that this is the best way to kill inventiveness.

If you don't have the guts to risk a sleepless night and spend a week restoring the damage you have done to the lab, you don't deserve to find answers.

Your self-righteousness is the true mark of self-important bureaucrats.

It does make me wonder what else they cannibalized from other people's work. Perhaps a review of these gentlemen's papers for plagiarism is in order? Or perhaps the grad student should keep an eye on their fiscal behavior and rat them out to the IRS?

True. But it's a lesson to remember: stealing research and materials from graduate students is far, far too common a practice. And it teaches the grad students to themselves steal research and materials from the next generation. I've had too many friends whose research was stolen by advisors or whose experiments were ruined by another professor in the same group "appropriating" their equipment, reserved laboratory time on expensive systems, or even their funding.Fascinating science with poor equipment is gr

Them destroying the ongoing work of another person just to save themselves a little bit of work shows a supreme lack of not only ethics but of decency.

I think this is getting a little blown out of proportion. The other person in this case is not an unrelated party. The downtrodden grad student was working at Lederman's direction, using equipment provided by Lederman, on projects set to Lederman's priorities. If Lederman decides, a 6pm on Friday night, that his priorities now favor a different direction,

I disagree that it's getting blown out of proportion.It's far too common for PhD's to destroy (or outright steal, as another has mentioned) the work of grad students for various reasons (such as they don't care, because they can and they enjoy it, to further themselves through someone else's work...)

It's great that the guy finally decided to do something right and include the grad student in the credits, but who's to say what the discoveries of the grad student might have lead to?

I believe the question is, did he actually repair the damage that he had done? Or he simply used the grad student's experiment because he thinks that a student's experiment is expendable and unimportant?

Risking someone else's sleepless nights is not a matter of genius and guts, or avoiding bureaucracy.

It is a matter of being an asshole, genius or not.

I agree with you about the 9-5, and the need to grasp inspiration on the spot to keep creativity alive.But that is no excuse to trample over other people's work without asking for their permission / collaboration.

You may be very convinced of your own genius and inventiveness. Good for you.But you might as well be destroying more important, time-consuming, work by other geniuses in the room.

If you don't have the guts to work the extra sleepless night setting up your own experiment, or (gasp) actually asking for the help if needed, then you really didn't deserve to find the answer.

Your self-righteousness is the true mark of self-important bureaucrats.

That remark reflects the arrogance of "genious." Did it ever occur to you that the bureaucracy exists because unchecked inventiveness, can do more harm than good. Or that "corporate drones" come in at 9 and leave past 5 because they have responsibilities, like taking care of their kids.I also get annoyed at the corporate hoop jumping to get something done, but I've also been on the other side of things cleaning up the mess of somebody

Your self-righteousness is the true mark of self-important bureaucrats.

That remark reflects the arrogance of "genious." Did it ever occur to you [...]

Doh! My 2am spelling is par for the course.

Many things occur to me all the time, but I can't stand "think-little" bureaucrat who can't see both sides of the equation. Here we have the usual/. case of self-righteousness being blindsided by facts. Many have told us the true story of that grad student which paints a different picture.

The thing about their story that got me was the fact that they decided they absolutely had to do this *right now* at 2am just to satisfy their own curiosity and were so self-absorbed that they killed the work a grad student had done in that particular lab in order to cannibalize his experiments so they didn't have to build everything themselves.

I don't get it: Fermilabs has published this story themselves, without any mention of how this student was compensated for having his work lost.

Judging from the fact that they didn't even *name* the graduate student whose work was so important to them that they just had to take it apart and use it, I'd say they probably didn't compensate him at all.I've known a number of PhD's and while some of them were very cool and worked with the other people in the building, there have been more than a few who thought that their work was the most important thing in the world and that it didn't matter what they did to get where they were going.

The name of Lederman's graduate assistant was Marcel Weinrich, which Lederman does credit as working with him on the project. Lederman, Garwin and Weinrich are all on the paper confirming the results on parity violation.

Couldn't the author of the slashdot post have at leased used the cut and paste features of his computer?

It's copy and paste -- when you cut and paste something, you remove it from one document and put it in another (or from one paragraph to another). When you copy and paste, it stays in the original place and a copy is placed in the second.

A chewing gum wrapper rotates the polarization of light that passes through it.

You can prove this with two polarizers at right angles if you crumple up a piece of chewing gum wrapper and stick it between them. When held up to a light source, only the light that goes through through the chewing gum wrapper makes it through the second polarizer- the rest is all dark. And since the rotation is frequency dependent, the chewing gum wrapper is glowing in multiple colors. Especially if you do a good job when you crumple it up. It would look great on TV.

When they say 'observer', they don't mean a physical observer, but a photon that is used to measure the effect. The wave function collapses as soon as a photon is used to measure the position/momentum of another particle.

I don't really think that is true, because if it were, wouldn't that essentially mean that no waveform could ever build up thanks to "observations" made by virtual particles (or, for that matter, electromagnetical interactions with particles on the other side of the universe)? Wouldn't it also mean that any compound particle, such as a molecule, an atom or even a proton automatically couldn't have a waveform, since its constituent parts would constantly "observe" each other?

Maybe I'm misunderstanding what you wrote, but it sounds like the same basic argument Einstein made against "spooky action at a distance". If I'm right, then you should read up about particle entanglement to see why it doesn't allow information to be transmitted FTL.

If quantum decoherence [wikipedia.org] is true, that ceases to be a problem. I'm really not the quantum physicist I'd like to be, but at least in my eyes, decoherence does seem to be a very appealing framework for explaining the waveform collapse.

Funny. It seems alive to half of us? Try logging in again and see if you get a different result. Look on the brightside. At least you don't have to catch another cat to retry this experiment. We're starting to run short in my neighborhood.

I once saw in a Popular Science magazine from around the 1940s a small note on building the Grand Coulee dam. They had to pull some cables through a long twisting tube that went through hundreds of meters of rock. No matter how they tried, they couldn't manage to push a pilot wire through all the bends. The solution: tie a string to the tail of a cat and send the cat into the tube. Simple, cheap, practical. The note even had a photo of the cat afterwards, he seemed quite happy.

A hundred meters of fishing line weighs a coupe of grams at most, if it didn't snag that would be no problem for the cat. The only problem I saw with that story is how to control the cat. He would probably lie down in the middle of the tube to sleep a few hours, before he got hungry. Then he would get out the same side he went in. That is, unless they pushed a small dog after him, but then the line would become a tangled mess. Well, maybe they first sent

It makes me think of an episode of Studio 60 where there's a missing poisonous snake under the stage. The animal handler then sends a ferret after it. Then the ferret wouldn't come out, so they send a coyote after it...

Maybe it would have been better to put an LED laser on the cat's head so he'd chase the point through the tube. Of course they didn't exist then, so the dog it is!

I can understand where you're coming from with the vaseline, the plastic wrap, and the Ovaltine jar. What disturbs me is the unknown idea in your head as to what you'd be using the spagetti for. Unless of course you want to "eat out" the synthetic pussy, and the taste of vaseline and Ovaltine just doesn't do it for ya.

I've put more thought into this than I really should have.

***Oh, how perfect, the word in the image I have to type to submit my post is insert.***

World-class detective Angus MacGyver of the hit 1980s television show MacGyver could jury-rig almost anything with duct tape and a pocket knife. High-energy physics labs demand as much and more from technicians and engineers, relying on their creativity and intelligence to navigate technical quagmires. And when a problem demands it, they deliver--engineering tiny cameras mounted on bocce balls that snake through 10,000 feet of steel piping; rigging a 13-ton cement block to bash deformed brass into shape; or aiming a high-powered laser around corners to unblock water lines. Unlike MacGyver's fixes--such as the fuse he repaired with a chewing-gum wrapper--some of these devices last.

An improvised grinderAn improvised grinder sanded welds along the long, straight sections of 10,000 feet of pipe at Fermilab. The sander within the rotating silver cylinder cleaned each weld.

Photo: Fred Ullrich, Fermilab

Leon Lederman, the Nobel Prize-winning former director of Fermilab, is a legendary lab MacGyver. He used a pocket knife, tape, and items on anyone's grocery list to confirm that interactions involving the weak force do not show perfect mirror symmetry, or parity, as scientists had long assumed. Just as a watch hand always sweeps clockwise, nuclei of atoms eject electrons in a preferred direction as they decay, rather than spraying them randomly. The technical term for this is "parity violation."

Intrigued by the experiments of Madame Chien-Shiung Wu, Lederman called his friend, Richard Garwin, to propose an experiment that would detect parity violation in the decay of the pi meson particle. That evening in January 1957, Lederman and Garwin raced to Columbia's Nevis laboratory and immediately began rearranging a graduate student's experiment into one they could use. "It was 6 p.m. on a Friday, and without explanation, we took the student's experiment apart," Lederman later recalled in an interview. "He started crying, as he should have."

The men knew they were onto something big. "We had an idea and we wanted to make it work as quickly as we could--we didn't look at niceties," Lederman said. And, indeed, niceties were overlooked. A coffee can supported a wooden cutting board, on which rested a Lucite cylinder cut from an orange juice bottle. A can of Coca-Cola propped up a device for counting electron emissions, and Scotch tape held it all together.

"Without the Swiss Army Knife, we would've been hopeless," Lederman said. "That was our primary tool."

Their first attempt, at 2 a.m., showed parity violation the instant before the Lucite cylinder--wrapped with wires to generate the magnetic field--melted.

"We had the effect, but it went away when the instrument broke," Lederman said. "We spent hours and hours fixing and rearranging the experiment. In due course, we got the thing going, we got the effect back, and it was an enormous effect. By six o'clock in the morning, we were able to call people and tell them that the laws of parity violate mirror symmetry," confirming the results of experiments led by Wu at Columbia University the month before.

Another giant figure in physics, founding Fermilab director Robert Wilson, is the hero of a widely circulated tale.

MacGyver-maniaMacGyver aired in more than 40 countries between 1985 and 1992, in some cases leaving a lasting imprint on the local language. In South Korea, for instance, call a knife a "Maekgaibeo kal" and people know you mean the Swiss Army-type knife the TV character carried. Malaysians call their pocket knives "Pisau MacGyvers" or just plain "MacGyver knives." In Norway and parts of Finland, duct tape is sometimes called "MacGyver tape."

Ernie Malamud, a physicist at Fermilab, remembers working with Wilson during his graduate studies at Cornell. The pair wanted to use helium gas, often used to fill balloons, to locate a leak in the glass vacuum chamber; but they discovered the hose from the

Hey I love MacGyver. I watched it as a kid and now I watch the DVDs with my fiancee who has fond memories of watching the show with her grandmother as a kid. However that doesn't stop me wincing at how bad the physics (and all the science is) in that show. Anyway it's not MacGyver physics unless there's a baddie waiting in the wings to kill MacGyver and the "experiment" foils their plan to do so, preferably causing the bad guy to fall flat on his ass or be blown up.

Seriously though. Why associate ingenuity with a tv show (even if it's a good one)? It's like describing math breakthroughs as "reminiscent of the TV show 'Numbers'". These shows are inspired by the real science more than they inspire it.

Some time ago I read an article about the science advisor for the show, IIRC a metallurgist. He said they made sure there was some critical thing missing to make sure that some kid doesn't go duplicate some dangerous thing in the show. So, it's a feature, not a bug.

They are simply referencing the premise of a show. You know how you just said you fondly remember watching the show as a kid? Perhaps these guys do too. All the while realizing the fact that said show made no excuse for its hooky interpretation of the rule of physics. They solved a physics puzzle with on-hand parts and said "Hey we're like MacGyver!"

It's why Superman can fly and stop trains by standing on the tracks and letting them slam into him with his hands out in front. People don't care about E=mc2 when they want to be entertained. The opposite is also true. No one cares if MacGyver's physics were accurate, it just was like "Whoa all MacGyver and shit!"

Since when was some poor student's experiment on people's weekly grocery list. Yes they used everyday items to modify the experiment which they took apart (causing the student to cry but apparently they weren't interested in "niceties").

Just like MacGyver. Look how MacGvyer creates a nuclear reaction with just this hammer, chisel, coke bottle, string, 300mL of acetone....oh and a nuclear reactor.

All I can say to suppliment my previous statement is that if the scientists don't have the ethics to not destroy someone else's work in order to further themselves, how can we trust them to be ethical with the really big stuff?

The old Ian Malcom quote from Jurassic Park comes to mind - "Your scientists were so busy seeing whether or not they could, they never stopped to think if they *should*."

When repairing some of the main computing systems, at Fermilab, I would joke that I needed a rubber chicken to repair the problem quickly, otherwise it would take a few hours. The one Christmas, one of the Ops staff bought me a pair of them. From then on, the joke was, when called at 3AM in the morning, did I have my chickens handy?

I don't know if this is mentioned in the article above (which appears to be slashdotted) but here's a scientist showing the force of gravity by creating a torsion balance using a ladder, fishing line and a few extras including two boules. (Yes, they're spelled 'boules')

... at the Rogers Commission hearings.C-clamp: $1.79Styrofoam cup of ice water: $.50Watching the expressions on the faces of NASA scientists who had inconclusive data from millions of dollars of testing? Priceless.

Also he allegedly was the only person to see the Trinity blast - as he figured the auto windshield glass would protect him from the UV, just as long as he ducked before the blast wave hit the glass.

Plus the one about Enrico Fermi at Trinity: he put some pieces of paper on the ground, scraped their start and finish positions in the sand with his toe, and based on the distance moved, the paper mass, and the distance to the blast, estimated the yield pretty darn close for that method.

We had Bob Tinker (founder of TERC & Concord Consortium) on our interactive satellite science telecast back in the late 80s.He was demo-ing some of the bank street labs software, including the graphical sound scope on the Apple ][.He did with a caller on the air, and when he recorded, we got some feedback from the open phone audio.Bob quickly realized that the echo was going up to the bird, back down to the caller, and thru the phone lines. Hmmmm.He quickly changed gears, told the caller to stay on the

It should be noted that parity is preserved; it just turns out that the opposite version occurs in anti-matter.

No that just means that parity is broken oppositely for matter and anti-matter. If you are refering to the combined symmetry i.e. doing a parity inversion followed by switching all matter from anti-matter then this is know as CP symmetry (C=charge conjugation [matter <-> antimatter] and P=parity).

Fortunately the CP symmetry is broken too but the effect is a lot smaller than parity viola